Man, the casino is so rigged. I just lost 12 spins of the slots in a row. So dumb since the casino is the only way to get any kind of money in the game.
Veloxe, it's not a glitch. It's what happens when they miss a checkpoint. They get sent back to the last one they crossed, which is why they disappear.
Get two Mysterious items of Death, and two of any of the items that raise health by 100 or 200%, and you're fine. You'll be doing over 1.5k damage per hit most of the time, and you'll still have the hp to stay alive. I used it to get through the game, and only died once.